Controllable growth of flowerlike ZnO nanostructures by combining laser direct writing and hydrothermal synthesis

Abstract

A method combing laser direct writing (LDW) and hydrothermal growth was developed for the synthesis of flowerlike three-dimensional (3D) ZnO nanostructures. By controlling the parameters of hydrothermal synthesis (reaction time and reaction temperature) and laser irradiation (pulse energy, irradiated time, and focus conditions), different sizes of flowerlike ZnO nanostructures are synthesized. Our results indicate that annealing the samples could reduce nonradiative related defects and greatly increase luminescence efficiency. The formation mechanisms of flowerlike ZnO nanostructures are also discussed. Such a mild synthesis route can be extended to fabricate complex 3D architectures of other materials.